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54 commits

Author SHA1 Message Date
unknown
3d2a74609a MWL#68 Subquery optimization: Efficient NOT IN execution with NULLs
This patch does three things:
- It adds the possibility to force the execution of top-level [NOT] IN
  subquery predicates via the IN=>EXISTS transformation. This is done by
  setting both optimizer switches partial_match_rowid_merge and
  partial_match_table_scan to "off".
- It adjusts all test cases where the complete optimizer_switch is
  selected because now we have two more switches.
- For those test cases where the plan changes because of the new available
  strategies, we switch off both partial match strategies in order to
  force the "old" IN=>EXISTS strategy. This is done because most of these
  test cases specifically test bugs in this strategy.

sql/opt_subselect.cc:
  Adds the possibility to force the execution of top-level [NOT] IN
  subquery predicates via the IN=>EXISTS transformation. This is done by
  setting both optimizer switches partial_match_rowid_merge and
  partial_match_table_scan to "off".
2010-03-11 23:43:31 +02:00
Sergey Petrunya
663773aa8c Subquery backport:
- More test results updates (checked)
2010-02-17 13:47:55 +03:00
Sergey Petrunya
64e63fb85d Subquery backport: Update test results (checked) 2010-02-12 00:56:02 +03:00
Sergey Petrunya
b83cb52e9e Backport of subquery optimizations to 5.3.
There are still test failures because of:
- Wrong query results in outer join + semi join
- EXPLAIN output differences
2010-01-17 17:51:10 +03:00